KR102343732B1 - Gel composition, cosmetic, and method for preparing a gel composition - Google Patents

Abstract

Provided is a gel composition that can be suitably used as a thickener for cosmetics and the like. 100 parts by mass of (meth)acrylic acid (a), 2.5 to 5 parts by mass of (meth)acrylic acid alkylester (b) having 18 to 24 carbon atoms in the alkyl group, and 0.1 parts by mass of compound (c) having two or more ethylenically unsaturated groups A gel composition comprising: a neutralized product of an alkyl-modified carboxyl group-containing polymer which is a copolymer of monomers comprising the following; and at least one of an anionic emulsifier and a nonionic emulsifier.

Description

Gel composition, cosmetic, and method for preparing a gel composition

The present invention relates to a gel composition that can be suitably used as a thickener for a cosmetic in the form of a viscous liquid or gel, used for hair care such as shampoo, body shampoo, and skin care such as face wash, for example, a method for producing the same, and the gel It relates to a cosmetic comprising the composition.

As cosmetic thickeners, for example, natural products such as xanthan gum, semi-synthetic compounds such as hydroxyethyl cellulose, and synthetic compounds such as carboxyvinyl polymer and alkyl-modified carboxyvinyl polymer are widely used. In particular, carboxyl group-containing polymers, such as carboxyvinyl polymers and alkyl-modified carboxyvinyl polymers, exhibit excellent thickening properties with a small amount of use, and are used in various cosmetics in that they can control the feeling of use.

As the carboxyl group-containing polymer, for example, a carboxyvinyl polymer obtained by reacting acrylic acid with pentaerythritol allyl ether as a crosslinking agent in a specific mixed solvent (see Patent Document 1), or a specific amount of an olefinically unsaturated carboxylic acid monomer and a specific amount of (meth ) A copolymer in which an acrylic acid alkyl ester (the number of carbon atoms in the alkyl group is 10 to 30) is reacted (see Patent Document 2), a specific amount of an olefinically unsaturated carboxylic acid monomer and a specific amount of (meth)acrylic acid alkyl ester (the number of carbon atoms in the alkyl group is 10-30) and a crosslinking agent (refer to Patent Document 3), a copolymer obtained by reacting an olefinic unsaturated carboxylic acid monomer with an (meth)acrylic acid alkyl ester (alkyl group having 8 to 30 carbon atoms) (Patent Document 4) Reference) and the like are known alkyl-modified carboxyvinyl polymers. Such a carboxyl group-containing polymer is usually dissolved in water or the like, then neutralized with an alkali component to obtain a neutralized viscous liquid of about 0.1 to 1 mass%, and used in cosmetics.

Such a neutralized viscous liquid has problems in that viscosity or stability is lowered or a part of the polymer is precipitated under the influence of an emulsifier, which is a main raw material constituting a cosmetic.

US Patent No. 5342911 Publication Japanese Patent Laid-Open No. Showa 51-6190 Japanese Patent Laid-Open No. Showa 59-232107 Specification of US Patent No. 5004598

The main object of the present invention is to provide a gel composition that can be suitably used as a thickener for cosmetics, a method for preparing the same, and a cosmetic comprising the gel composition.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly examined in order to solve the said subject. As a result, 100 parts by mass of (meth)acrylic acid (a), 2.5 to 5 parts by mass of (meth)acrylic acid alkylester (b) having 18 to 24 carbon atoms in the alkyl group, and a compound (c) having two or more ethylenically unsaturated groups A gel composition comprising a neutralized product of an alkyl-modified carboxyl group-containing polymer, which is a copolymer of a monomer containing 0.1 parts by mass or less, and at least one of an anionic emulsifier and a nonionic emulsifier, at least one of an anionic emulsifier and a nonionic emulsifier It was found that the viscosity difference was very large before and after mixing. For this reason, in the low viscosity state before mixing the anionic emulsifier or the nonionic emulsifier, the desired component can be dispersed and dissolved with high uniformity, and then at least one of the anionic emulsifier and the nonionic emulsifier It was found that a gel composition having a high viscosity can be appropriately obtained by adding . The gel composition has excellent thickening properties and can be suitably used as a thickener for cosmetics and the like.

That is, the present invention provides an invention having the following configuration.

Item 1. (meth)acrylic acid (a) 100 parts by mass, (meth)acrylic acid alkylester (b) having 18 to 24 carbon atoms in the alkyl group (b) 2.5 to 5 parts by mass, and compound (c) having two or more ethylenically unsaturated groups A gel composition comprising: a neutralized product of an alkyl-modified carboxyl group-containing polymer that is a copolymer of a monomer containing 0.1 parts by mass or less; and at least one of an anionic emulsifier and a nonionic emulsifier.

Item 2. The gel composition according to Item 1, wherein the content of the anionic emulsifier is in the range of 0.05 mass% to 1 mass% (solid content) and the pH is in the range of 4 to 5.6.

Item 3. The gel composition according to Item 1, wherein the content of the nonionic emulsifier is in the range of 0.05 mass% to 1 mass% (solid content) and the pH is in the range of 4 to 13.

Item 4. Item 1, wherein the compound (c) having two or more ethylenically unsaturated groups is at least one selected from the group consisting of pentaerythritol allyl ether, diethylene glycol diallyl ether, polyethylene glycol diallyl ether and polyallyl saccharose. The gel composition according to any one of claims to 3.

Item 5. The gel composition according to any one of Items 1 to 4, wherein the anionic emulsifier is an alkyl sulfate, and the nonionic emulsifier is a polyoxyethylene alkyl ether.

Item 6. A cosmetic comprising the gel composition according to any one of Items 1 to 5.

Item 7. (meth)acrylic acid (a) 100 parts by mass, (meth)acrylic acid alkylester (b) having 18 to 24 carbon atoms in the alkyl group (b) 2.5 to 5 parts by mass, and compound (c) having two or more ethylenically unsaturated groups A step of mixing an alkyl-modified carboxyl group-containing polymer that is a copolymer of a monomer containing 0.1 parts by mass or less and an alkali component to prepare a neutralized product of the alkyl-modified carboxyl group-containing polymer, and

mixing the neutralized product of the alkyl-modified carboxyl group-containing polymer with at least one of an anionic emulsifier and a nonionic emulsifier;

A method for producing a gel composition comprising a.

According to the present invention, it is possible to provide a gel composition that can be suitably used as a thickener for cosmetics and the like, and a method for producing the same.

The gel composition of the present invention contains 100 parts by mass of (meth)acrylic acid (a), 2.5 to 5 parts by mass of (meth)acrylic acid alkylester (b) having 18 to 24 carbon atoms in the alkyl group, and a compound having two or more ethylenically unsaturated groups (c) a neutralized product of an alkyl-modified carboxyl group-containing polymer, which is a copolymer of a monomer containing 0.1 parts by mass or less, and at least one of an anionic emulsifier and a nonionic emulsifier. Hereinafter, the gel composition of the present invention, its manufacturing method, and cosmetics including the gel composition will be described in detail.

In the present invention, “acrylic acid and methacrylic acid” are collectively referred to as “(meth)acrylic acid”. In the present invention, "neutralized viscous liquid" refers to an aqueous dispersion of an alkyl-modified carboxyl group-containing polymer such that the pH of the aqueous dispersion of the alkyl-modified carboxyl group-containing polymer becomes a predetermined value (normally, the pH is about 3.5 to 6.5). It means a viscous liquid obtained by mixing components (eg, alkali metal hydroxides such as sodium hydroxide, amines such as triethanolamine and diisopropanolamine). In addition, "1 mass % neutralized viscous liquid" means a neutralized viscous liquid in which the ratio of the neutralized product of the alkyl-modified carboxyl group-containing polymer is 1 mass %.

In the present invention, the neutralized product of the alkyl-modified carboxyl group-containing polymer is a compound in which the alkyl-modified carboxyl group-containing polymer is partially or completely neutralized with an alkali component as described above. In the gel composition of the present invention (especially when the pH is about 3.5 to 6.5), the neutralized product of the alkyl-modified carboxyl group-containing polymer is usually a partially neutralized product of the alkyl-modified carboxyl group-containing polymer. In addition, the pH before neutralizing an alkyl-modified carboxyl group containing polymer is about 2.5-3 normally.

The alkyl-modified carboxyl group-containing polymer contains 100 parts by mass of (meth)acrylic acid (hereinafter, may be referred to as component (a)) and (meth)acrylic acid alkyl ester having 18 to 24 carbon atoms in the alkyl group (hereinafter referred to as component (b)) It is a copolymer of 2.5 to 5 parts by mass and 0.1 parts by mass or less of a compound having two or more ethylenically unsaturated groups (hereinafter, may be referred to as component (c)). That is, in the alkyl-modified carboxyl group-containing polymer of the present invention, at least components (a) and (b) are copolymerized, and if necessary, the component (c) is also copolymerized.

As (meth)acrylic acid (component (a)) in the present invention, at least one of acrylic acid and methacrylic acid can be used.

The (meth)acrylic acid alkylester (component (b)) having 18 to 24 carbon atoms in the alkyl group is an ester of (meth)acrylic acid and a higher alcohol having 18 to 24 carbon atoms in the alkyl group. Specific examples of component (b) include esters of (meth)acrylic acid and stearyl alcohol (that is, stearyl (meth)acrylic acid), esters of (meth)acrylic acid and eicosanol (that is, eicosanyl (meth)acrylic acid), ( esters of meth)acrylic acid and behenyl alcohol (ie, behenyl (meth)acrylic acid), esters of (meth)acrylic acid and tetracosanyl (ie, tetracosanyl (meth)acrylic acid), and the like. Among them, stearyl methacrylate, methacrylic acid, from the viewpoint that the thickening effect of the highly transparent gel composition is excellent even in the coexistence of a neutralized product of an alkyl-modified carboxyl group-containing polymer and a cationic polymer that is often blended in cosmetics, etc. Acid eicosanyl, behenyl methacrylate, tetracosanyl methacrylate and the like are suitably used.

Alkyl-modified carboxyl group-containing polymer WHEREIN: One type may be used for the component (b) which comprises a monomer, and may use two or more types. When copolymerizing using two or more types of component (b), for example, Nippon Yushi Co., Ltd. brand name Q BLEMMER VMA-70 (stearyl methacrylate 10 parts by mass to 20 parts by mass, methacrylic acid A mixture of 10 parts by mass to 20 parts by mass of eicosanil, 59 parts by mass to 80 parts by mass of behenyl methacrylate, and 1 part by mass or less of tetracosanyl methacrylate) can be used.

The ratio of the component (b) in an alkyl-modified carboxyl group-containing polymer is 2.5 mass parts - 5 mass parts with respect to 100 mass parts of (meth)acrylic acid (component (a)). In the coexistence of at least one of an anionic emulsifier and a nonionic emulsifier, from the viewpoint of effectively increasing the viscosity of the gel composition, the proportion of component (b) is preferably 1 to 3 parts by mass relative to 100 parts by mass of component (a). A mass part is mentioned. Further, when the proportion of component (b) is less than 2.5 parts by mass relative to 100 parts by mass of component (a), in the presence of at least one of an anionic emulsifier and a nonionic emulsifier, the viscosity of the gel composition tends to be low, and on the other hand, Even when it exceeds 5 mass parts, the viscosity of a gel composition becomes low easily.

The compound (component (c)) which has two or more ethylenically unsaturated groups is a compound which has two or more ethylenically unsaturated groups which have polymerizability. In the present invention, the component (c) constitutes a monomer of the alkyl-modified carboxyl group-containing polymer if necessary. Preferred specific examples of component (c) include polyallyl ethers of pentaerythritol, such as pentaerythritol diallyl ether, pentaerythritol triallyl ether, and pentaerythritol tetraallyl ether (each of these and a mixture of two or more types are referred to as "pentaerythritol allyl ether" generically), diethylene glycol diallyl ether, polyethylene glycol diallyl ether, polyallyl saccharose, and the like. Alkyl-modified carboxyl group-containing polymer WHEREIN: 1 type may be sufficient as the component (c) which comprises a monomer as needed, and 2 or more types may be sufficient as it.

As the ratio of component (c) in the alkyl-modified carboxyl group-containing polymer, 0.1 parts by mass or less, preferably 0.0001 to 0.05 parts by mass, more preferably 100 parts by mass of (meth)acrylic acid (component (a)) 0.001-0.044 mass parts is mentioned. When the proportion of component (c) exceeds 0.1 parts by mass, the viscosity of the gel composition tends to decrease, and there is a fear that the stability of the cosmetic using the gel composition may deteriorate.

In the alkyl-modified carboxyl group-containing polymer of the present invention, monomers other than the above-mentioned components (a) to (c) (other monomers copolymerizable with at least one of components (a) to (c)) may be copolymerized. For example, (meth)acrylic acid lauryl can also be used in the ratio of more than 0 mass parts and 1 mass part or less with respect to 100 mass parts of total amounts of components (a)-(c). Further, in the present invention, the total ratio of components (a) to (c) in the monomer constituting the alkyl-modified carboxyl group-containing copolymer is not particularly limited, but preferably 50 mass% or more, more preferably 80 mass% % - about 100 mass %, More preferably, about 90 mass % - about 100 mass %, Especially preferably, about 95 mass % - about 100 mass % is mentioned. The total ratio may be substantially 100 mass %.

Although not particularly limited to the method for producing the alkyl-modified carboxyl group-containing polymer, a solution containing at least the above-mentioned components (a) and (b), and a solution in which a polymerization initiator is added to a solvent is heated while stirring in an inert gas atmosphere, , a polymerization method, and the like.

Although not particularly limited as an inert gas for obtaining an inert gas atmosphere, there are nitrogen gas, argon gas, and the like.

The solvent is not particularly limited as long as it dissolves at least the component (a) and the component (b), but does not dissolve the resulting alkyl-modified carboxyl group-containing polymer and does not inhibit the copolymerization reaction. Specific examples of the solvent include hydrocarbon solvents such as n-pentane, n-hexane, n-heptane, cyclopentane, and cyclohexane; and ester solvents such as methyl acetate, ethyl acetate, propyl acetate, and butyl acetate. A solvent may be used by 1 type, and may be used in combination of 2 or more type. Among these solvents, normal hexane, normal heptane, ethyl acetate and the like are suitably used.

It is preferable that the usage-amount of a solvent sets it as 300 mass parts - 5,000 mass parts with respect to 100 mass parts of component (a) from a viewpoint of the improvement of stirring operability and economical efficiency.

As the polymerization initiator, for example, a radical polymerization initiator is preferable. Specific examples of the polymerization initiator include α,α′-azoisobutyronitrile, 2,2′-azobis(2,4-dimethylvaleronitrile), 2,2′-azobis(methylisobutylate), and the like. have. Among these, 2,2'-azobis(methyl isobutylate) is preferable from a viewpoint of being easy to obtain a high molecular weight alkyl-modified carboxyl group-containing polymer. A polymerization initiator may be used by 1 type, and may be used in combination of 2 or more type.

The amount of the polymerization initiator used is preferably about 0.00003 mol to 0.002 mol with respect to 1 mol of component (a) from the viewpoint of appropriately maintaining the reaction rate. Since the usage-amount of a polymerization initiator is 0.00003 mol or more, the reaction rate does not become slow too much, and it is economical. Moreover, since the usage-amount of a polymerization initiator is 0.002 mol or less, it suppresses superposition|polymerization from advancing rapidly, and control of a polymerization reaction becomes easy.

The polymerization temperature is preferably about 50°C to 90°C, more preferably about 55°C to 75°C, from the viewpoint of appropriately maintaining the reaction rate.

The polymerization time varies depending on the polymerization temperature and the like, but is usually about 0.5 to 5 hours.

In the dispersion liquid after polymerization, from the viewpoint of shortening the drying time and suppressing the agglomeration of the copolymer, for example, by heating to 80 ° C. to 130 ° C. to remove the solvent, an alkyl-modified carboxyl group-containing polymer can be obtained. The drying time can be shortened by making the heating temperature at this time into 80 degreeC or more. Moreover, the fall of the dispersibility with respect to the water of an alkyl-modified carboxyl group containing polymer can be suppressed suitably by heating temperature being 130 degreeC or less.

From the viewpoint of increasing the viscosity and transparency of the gel composition and increasing the viscosity difference before and after mixing with the anionic emulsifier and the nonionic emulsifier, even in the presence of at least one of an anionic emulsifier and a nonionic emulsifier, alkyl modification The carboxyl group-containing polymer (which is not present in the coexistence of at least one of an anionic emulsifier and a nonionic emulsifier) preferably has a viscosity of 5,000 mPa·s or less at 25°C when 1 mass% neutralized viscous liquid, and 100 to 1000 mPa It is more preferable that it is about s.

In addition, in this invention, a viscosity means the value measured by the method described in an Example.

In the gel composition of the present invention, the content of the neutralized product of the alkyl-modified carboxyl group-containing polymer is not particularly limited, but is preferably about 0.1 mass% to 2 mass%, more preferably about 0.5 mass% to 1.5 mass%. have.

From the viewpoint of increasing the viscosity of the gel composition in the coexistence of an anionic emulsifier with a neutralized product of the aforementioned alkyl-modified carboxyl group-containing polymer, preferably polyoxyethylene (hereinafter, sometimes abbreviated as POE) sodium lauryl ether sulfate , polyoxyethylene alkyl ether sulfates such as POE isodecyl ether ammonium sulfate; polyoxyethylene alkyl ether phosphate esters such as POE lauryl ether phosphate and POE tridecyl ether phosphate; Ammonium lauryl sulfate, amomnium laureth sulfate, triethylamine lauryl sulfate, triethylamine laureth sulfate, triethanolamine lauryl sulfate, triethanolamine laureth sulfate, monoethanolamine lauryl sulfate, laureth alkyl sulfates such as monoethanolamine sulfate, diethanolamine lauryl sulfate, diethanolamine laureth sulfate, sodium lauryl sulfate, sodium laureth sulfate, potassium laureth sulfate, and potassium lauryl sulfate; sulfonic acid salts such as sodium dodecylbenzenesulfonate; sulfosuccinates such as sodium dioctylsulfosuccinate; Fatty acid salts, such as potassium laurate and sodium stearate, etc. are mentioned. Among them, it is preferable to use lauryl sulfate such as sodium lauryl sulfate and laureth sulfate such as sodium laureth sulfate from the viewpoint of foaming well and obtaining a conditioning effect when the gel composition of the present invention is formulated into a cosmetic. . These anionic emulsifiers may be used individually by 1 type, respectively, and may be used in combination of 2 or more type.

In addition, from the viewpoint of increasing the viscosity of the gel composition in the presence of a neutralized product of the aforementioned alkyl-modified carboxyl group-containing polymer as a nonionic emulsifier, preferably polyoxyethylene lauryl ether, POE tridecyl ether, POE cetyl ether , polyoxyethylene alkyl ethers such as POE stearyl ether; polyoxyethylene polyoxypropylene (hereinafter, may be abbreviated as POP) lauryl ether, POE/POP cetyl ether, and polyoxyethylene/polyoxypropylene alkyl ether such as POE/POP stearyl ether; polyoxyethylene sorbitan fatty acid esters such as POE sorbitan monooleate, POE sorbitan monostearate, and POE sorbitan distearate; Polyoxyethylene sorbit fatty acid ester, such as POE sorbit monooleate, POE sorbit monostearate, and POE sorbit distearate; polyoxyethylene glycerin fatty acid esters such as POE glycerin monooleate, POE glycerin monostearate, and POE glycerin distearate; polyoxyethylene fatty acid esters such as POE monooleate, POE monostearate, and POE distearate; polyoxyethylene castor oil derivatives such as POE castor oil, POE hydrogenated castor oil, POE hydrogenated castor oil monolaurate, and POE hydrogenated castor oil monoisostearate; polyoxyethylene alkylamines such as POE laurylamine and POE stearylamine; Sucrose fatty acid esters, such as sucrose lauric acid ester and sucrose myristic acid ester, etc. are mentioned. Among them, it is preferable to use polyoxyethylene lauryl ether or the like in terms of foaming well, hypoallergenicity, and obtaining a conditioning effect when the gel composition of the present invention is blended into a cosmetic. These nonionic emulsifiers may be used individually by 1 type, respectively, and may be used in combination of 2 or more type.

Moreover, in this invention, an anionic emulsifier and a nonionic emulsifier can be used together.

In the gel composition of the present invention, the content of the anionic emulsifier and the nonionic emulsifier, for example, even when the pH of the gel composition of the present invention is set low (for example, the pH is in the range of 4 to 5.6). From the viewpoint of exhibiting high viscosity characteristics, the content of the anionic emulsifier is preferably about 0.05 mass% to 1 mass% (solid content), more preferably about 0.1 mass% to 0.5 mass% (solid content). . In addition, from the viewpoint of exhibiting high viscosity characteristics even when the pH of the gel composition of the present invention is set in a wide range (for example, the pH is in the range of about 4 to 13), the content of the nonionic emulsifier is preferably is about 0.05 mass% to 1 mass% (solid content), more preferably about 0.1 mass% to 0.5 mass% (solid content).

In the gel composition of the present invention, for example, by setting the amount of the anionic emulsifier to about 0.05 mass% to 1 mass% (solid content), more preferably about 0.1 mass% to 0.5 mass% (solid content), the pH is It can be a high-viscosity gel composition under a low pH in the range of 4 to 5.6, and can be suitably used as a thickener for cosmetics and the like. In addition, since the gel composition of the present invention has a particularly large difference in viscosity before and after adding the anionic emulsifier in such a low pH range, for example, in a low viscosity state before adding the anionic emulsifier, various By mixing the components uniformly, and then adding an anionic emulsifier, it is possible to obtain a gel composition with a suitable high viscosity in a low pH range.

Further, in the gel composition of the present invention, for example, by setting the amount of the nonionic emulsifier to about 0.05 mass % to 1 mass % (solid content), more preferably about 0.1 mass % to 0.5 mass % (solid content), It can be a high-viscosity gel composition under a wide pH range of pH 4 to 13, and can be suitably used as a thickener for cosmetics and the like. In addition, the gel composition of the present invention has a particularly large difference in viscosity before and after adding the nonionic emulsifier in such a wide pH range. By mixing and then adding a nonionic emulsifier, a gel composition having a suitable high viscosity in a low pH range can be obtained.

In the gel composition of the present invention, when the pH is as small as 4 to 5.6, the content of the anionic emulsifier is about 0.05 mass % to 1 mass % (solid content), and the viscosity is, for example, 15,000 mPa·s or more, and further 20,000 mPa It can be more than s. In addition, as an upper limit of the viscosity in this case, it is about 200,000 mPa*s normally.

In addition, in the gel composition of the present invention, the content of the nonionic emulsifier is about 0.05 mass % to 1 mass % (solid content) in a wide range such as pH 4 to 13, and the viscosity is, for example, 20,000 mPa·s or more. , and may furthermore be 30,000 mPa·s or more. In addition, as an upper limit of the viscosity in this case, it is about 200,000 mPa*s normally.

Although the detail of the mechanism which the gel composition of this invention is equipped with high viscosity and can be used suitably as a thickener for cosmetics etc. is not necessarily clear, for example, it can consider as follows. That is, in the present invention, the neutralized product of the alkyl-modified carboxyl group-containing polymer contained in the gel composition is copolymerized with the aforementioned components (a) to (c) in the predetermined amount, so that the neutralized product of the alkyl-modified carboxyl group-containing polymer; Since at least one of the anionic emulsifier and the nonionic emulsifier appropriately forms an association in water and thickens, it is considered that the gel composition has a high viscosity.

The gel composition of the present invention usually contains water in addition to components (a) to (c). Although the water content in the gel composition of this invention is not specifically limited, 91.4-99.3 mass % is preferable, More preferably, it is 92.0-99.0 mass %.

In addition, the gel composition of the present invention may contain other thickeners, alcohols, pH adjusters, humectants, emulsions, salts, cationic surfactants, amphoteric surfactants, chelating agents, preservatives, antioxidants, and ultraviolet absorbers, within the scope not impairing the purpose thereof. , various additives such as colorants and fragrances may also be included. The gel composition of the present invention can be suitably used as a thickener for cosmetics in the form of viscous liquids or gels used for hair care such as shampoo, skin care such as body shampoo and face wash, and the like. The cosmetic of the present invention contains the gel composition of the present invention, and may further contain various cosmetic ingredients to be blended into the cosmetic.

Although it does not restrict|limit especially to the manufacturing method of the gel composition of this invention, For example, it can manufacture suitably by the manufacturing method provided with the following process.

100 parts by mass of (meth)acrylic acid (a), 2.5 to 5 parts by mass of (meth)acrylic acid alkylester (b) having 18 to 24 carbon atoms in the alkyl group, and 0.1 parts by mass of compound (c) having two or more ethylenically unsaturated groups A step of preparing a neutralized product of the alkyl-modified carboxyl group-containing polymer by mixing the above-mentioned alkyl-modified carboxyl group-containing polymer and the alkali component, which is a copolymer of a monomer comprising the following.

A step of mixing the neutralized product of the alkyl-modified carboxyl group-containing polymer with at least one of the anionic emulsifier and the nonionic emulsifier.

In addition, in the above production method, the pH of the gel composition can be adjusted to a desired value by adding an alkali component before and after mixing at least one of the anionic emulsifier and the nonionic emulsifier.

In the method for producing the gel composition of the present invention, various additives may be mixed. Various additives may be mixed both before and after mixing the neutralized product of the alkyl-modified carboxyl group-containing polymer and at least one of an anionic emulsifier and a nonionic emulsifier.

Example

The present invention will be described in detail with reference to Examples and Comparative Examples below. However, the present invention is not limited to the Examples.

(viscosity measurement)

Spindle rotor No. at 25°C using a BH type rotational viscometer. The viscosity was measured after 1 minute at a rotation speed of 7 at 20 revolutions per minute.

(Production Example 1)

45 g (0.625 mol) of acrylic acid, Blemmer VMA70 (manufactured by Nihon Yushi Corporation: 10 to 20 parts by mass of stearyl methacrylate, methacrylic acid in a 500 mL 4-neck flask equipped with a stirrer, thermometer, nitrogen blowing tube and cooling tube) A mixture containing 10 to 20 parts by mass of eicosanil acid, 59 to 80 parts by mass of behenyl methacrylate, and 1 part by mass or less of tetracosanyl methacrylate) 1.4 g, pentaerythritol allyl ether (pentaerythritol triallyl) A mixture of ether and pentaerythritol tetraallyl ether) 0.02 g, n-hexane 150 g and 2,2'-azobis methyl isobutyrate 0.081 g (0.00035 mol) were added. Thereafter, nitrogen gas was blown into the solution in order to remove oxygen in the flask while uniformly stirring the contents of the flask. After that, in order to heat the contents in a state in which stirring and nitrogen gas were continuously blown, the oil bath setting was set to 60 to 65° C. and maintained for 4 hours. Then, the oil bath set temperature was set to 90 degreeC, and normal hexane was removed. Thereafter, the contents of the flask were transferred to a reduced pressure dryer (manufactured by Yamatho, vacuum constant temperature dryer DP33), the set temperature of the dryer was set to 110° C., the set pressure was set to 10 mmHg, and dried for 8 hours. 45 g of containing polymer (Polymer 1) was obtained.

(Production Example 2)

In Production Example 1, the amount of Blemmer VMA70 (manufactured by Nippon Yushi Co., Ltd.) was changed to 1.125 g, and the amount of pentaerythritol allyl ether (a mixture of pentaerythritol triallyl ether and pentaerythritol tetraallyl ether) was changed from 0.02 g to 0.135. In the same manner as in Production Example 1 except for changing to g, 45 g of an alkyl-modified carboxyl group-containing polymer (Polymer 2) in the form of a white fine powder was obtained.

<Evaluation of relationship between pH and viscosity of gel composition>

(Reference Example 1)

Using a high-speed stirring system TK ROBOMIX (manufactured by Primix Co., Ltd.) with a disper blade (Φ 40 mm) adjusted, 10 g of Polymer 1 was placed in a 2 L beaker containing 987.7 g of distilled water at 5000 revolutions per minute Under a stirring speed of After stirring at 5000 rotations for 10 minutes, the stirring speed was reduced to 3000 rotations per minute and stirring was continued for 20 minutes. Thereafter, 2.3 g of an 18% by mass aqueous sodium hydroxide solution was added at a stirring rate of 1400 revolutions per minute, and the mixture was stirred until the contents became uniform to prepare a neutralized viscous liquid having a pH of about 3.8. Next, by adding a predetermined amount of 18 mass % sodium hydroxide aqueous solution and uniformly stirring, the pH was changed as shown in Table 1, and the viscosity at each pH of the neutralized viscous solution was measured (emulsifier content 0 in Table 1) mass%). A result is shown in Table 1.

[Table 1]

(Examples 1 to 4)

In the same manner as in Reference Example 1, 144 g of the neutralized viscous liquid adjusted to about pH 3.8 of Polymer 1 was subdivided into a 200 L beaker, and using 4 paddle blades (Φ50 mm) at a stirring speed of 500 revolutions per minute, Each content (sodium lauryl sulfate content or sodium laureth sulfate content respectively 0.1 mass % (solid content), 0.50 mass % (solid content)) was made to be sodium lauryl sulfate (Emar 10G manufactured by Kao Co., Ltd., sodium lauryl sulfate 98 mass %), distilled water, sodium laureth sulfate (Emar 20C manufactured by Kao Co., Ltd., sodium laureth sulfate 25% by mass) and distilled water (each such that the gel composition is 150 g) are slowly added, and the stirring speed is increased to 1000 revolutions per minute to 1 Each gel composition was prepared by mixing with time. Next, a predetermined amount of an 18 mass % aqueous sodium hydroxide solution was added to the obtained gel composition and uniformly stirred, the pH was changed as shown in Table 2, and the viscosity at each pH of the neutralized viscous solution was measured. A result is shown in Table 2.

[Table 2]

As is clear from the results shown in Table 2, in Examples 1 to 4, it can be seen that under a low pH of about 4 to 5.6, a gel composition with high viscosity is obtained. In addition, since the difference in viscosity before and after the addition of the anionic emulsifier is very large, the various components are uniformly mixed in a low viscosity state before the addition of the anionic emulsifier, and then the anionic emulsifier is added to suitably in a low pH range. It can be seen that a high-viscosity gel composition can be prepared. That is, before the addition of the anionic emulsifier in the low pH range (the emulsifier content of 0% by mass in Table 1 (Reference Example 1)), the viscosity of the composition is very low, and it is possible to easily uniformly disperse and dissolve each component, , and then adding a predetermined amount of anionic emulsifier (sodium lauryl sulfate content or sodium laureth sulfate content of 0.1 mass% and 0.50 mass%, respectively), it can be seen that a high viscosity gel composition can be obtained.

(Reference Example 2)

A neutralized viscous liquid having a pH of about 3.8 was prepared in the same manner as in Reference Example 1 except that Polymer 2 was used instead of Polymer 1. Next, by adding a predetermined amount of 18% by mass aqueous sodium hydroxide solution and uniformly stirring, the pH was changed as shown in Table 3, and the viscosity at each pH of the neutralized viscous solution was measured (emulsifier content 0 in Table 3) mass%). A result is shown in Table 3.

[Table 3]

(Comparative Example 1)

In the same manner as in Reference Example 2, 144 g of a neutralized viscous solution adjusted to a pH of about 3.8 in Polymer 2 (a polymer having a high degree of crosslinking compared to Polymer 1) was subdivided into a 200L beaker, and 4 paddle blades (Φ50mm) were used to Under a stirring speed of 500 revolutions per minute, sodium lauryl sulfate (Emar 10G manufactured by Kao Corporation, sodium lauryl sulfate 98 mass%) was made to the content shown in Table 4 (sodium lauryl sulfate content 0.1 mass % (solid content)), and Distilled water (amount to make 150 g of gel composition = 5.85 g) was slowly added, and the stirring speed was increased to 1000 revolutions per minute and mixed for 1 hour to prepare a gel composition. Next, a predetermined amount of an 18 mass % aqueous sodium hydroxide solution was added to the obtained gel composition and uniformly stirred, the pH was changed as shown in Table 4, and the viscosity at each pH of the neutralized viscous solution was measured. A result is shown in Table 4.

[Table 4]

As is clear from the results shown in Tables 3 and 4, as in Reference Example 2, when Polymer 2 (a polymer having a high crosslinking degree compared to Polymer 1) was used, an anionic emulsifier was added in a low pH range of pH 4 to 5.6. Since the viscosity before the following (0 mass % of the emulsifier content in Table 3 (Reference Example 2)) is high, compared with Examples 1 to 4, it can be seen that it is difficult to uniformly disperse and dissolve each component. It can be seen that also in Comparative Example 1 in which an anionic emulsifier was further added to Reference Example 2, the viscosity of the gel composition did not rise much.

(Examples 5 and 6)

In the same manner as in Reference Example 1, 144 g of the neutralized viscous liquid having polymer 1 adjusted to pH 3.8 was subdivided into a 200 L beaker, and using 4 paddle blades (Φ 50 mm) at a stirring speed of 500 revolutions per minute, each content listed in Table 5 (Polyoxyethylene lauryl ether content of 0.1 mass % (solid content) and 0.50 mass % (solid content), respectively)) 100% by mass) and distilled water (each in an amount such that the gel composition is 150 g) were slowly added, the stirring speed was increased to 1000 revolutions per minute, and the mixture was mixed for 1 hour to prepare each gel composition. Next, a predetermined amount of an 18 mass % aqueous sodium hydroxide solution was added to the obtained gel composition and uniformly stirred, pH was changed as shown in Table 5, and the viscosity at each pH of the neutralized viscous solution was measured. A result is shown in Table 5.

[Table 5]

As is clear from the results shown in Table 5, it can be seen that in Examples 5 and 6, the pH is in a wide range of about 4 to 13, and a high viscosity gel composition is obtained. In addition, since the difference in viscosity before and after adding the nonionic emulsifier is very large, the various components are uniformly mixed in a low viscosity state before the nonionic emulsifier is added, and then the nonionic emulsifier is added, resulting in a wide It can be seen that a gel composition having a high viscosity can be prepared appropriately in the pH range. That is, before adding the nonionic emulsifier in a wide pH range (the emulsifier content of 0% by mass in Table 1 (Reference Example 1)), the viscosity of the composition is very low, and it is easy to uniformly disperse and dissolve each component. It can be seen that a high viscosity gel composition can be obtained by adding a predetermined amount of a nonionic emulsifier after that (each polyoxyethylene lauryl ether content is 0.1 mass% (solid content) and 0.50 mass% (solid content)) can

(Comparative Example 2)

In the same manner as in Reference Example 2, 144 g of a neutralized viscous liquid adjusted to a pH of about 3.8 in Polymer 2 (a polymer having a high crosslinking degree compared to Polymer 1) was subdivided into a 200L beaker, and 500 rotations per minute using 4 paddle blades (Φ50mm) Polyoxyethylene lauryl ether (Emarugen 108 manufactured by Kao Corporation, polyoxyethylene la 100% by mass of uryl ether) and distilled water (the amount of which the gel composition becomes 150 g = 5.25 g) were slowly added, the stirring speed was increased to 1000 revolutions per minute, and the mixture was mixed for 1 hour to prepare a gel composition. Next, a predetermined amount of an 18 mass % aqueous sodium hydroxide solution was added to the obtained gel composition and uniformly stirred, the pH was changed as shown in Table 6, and the viscosity at each pH of the neutralized viscous solution was measured. A result is shown in Table 6.

[Table 6]

As is clear from the results shown in Table 3 and Table 6, as in Reference Example 2, when Polymer 2 (a polymer having a higher crosslinking degree compared to Polymer 1) was used, the nonionic emulsifier was used in a wide range of pH 4 to 12. It can be seen that, compared with Examples 5 and 6, it is difficult to uniformly disperse and dissolve each component because the viscosity before addition (0 mass % of the emulsifier content in Table 3 (Reference Example 2)) is high. When a nonionic emulsifier is added here (Comparative Example 2), the viscosity increases in the pH range of 4 to 12, but since the viscosity before adding the nonionic emulsifier is too high, it can be said that the gel composition is difficult to use.

Claims (7)

100 parts by mass of (meth)acrylic acid (a), 2.5 to 5 parts by mass of (meth)acrylic acid alkylester (b) having 18 to 24 carbon atoms in the alkyl group, and 0.1 parts by mass of compound (c) having two or more ethylenically unsaturated groups A neutralized product of an alkyl-modified carboxyl group-containing polymer, which is a copolymer of a monomer comprising the following, and at least one of an anionic emulsifier and a nonionic emulsifier,
The content of the anionic emulsifier is in the range of 0.05% by mass to 1% by mass (solid content), and the pH is in the range of 4 to 5.6,
The gel composition, wherein the content of the nonionic emulsifier is in the range of 0.05 mass% to 1 mass% (solid content), and the pH is in the range of 4 to 13. delete delete The method of claim 1,
The gel composition, wherein the compound (c) having two or more ethylenically unsaturated groups is at least one selected from the group consisting of pentaerythritol allyl ether, diethylene glycol diallyl ether, polyethylene glycol diallyl ether and polyallyl saccharose. The method of claim 1,
The gel composition, wherein the anionic emulsifier is an alkyl sulfate, and the nonionic emulsifier is polyoxyethylene alkyl ether. A cosmetic comprising the gel composition according to any one of claims 1, 4 and 5. 100 parts by mass of (meth)acrylic acid (a), 2.5 to 5 parts by mass of (meth)acrylic acid alkylester (b) having 18 to 24 carbon atoms in the alkyl group, and 0.1 parts by mass of compound (c) having two or more ethylenically unsaturated groups A step of preparing a neutralized product of the alkyl-modified carboxyl group-containing polymer by mixing an alkyl-modified carboxyl group-containing polymer, which is a copolymer of a monomer comprising the following, with an alkali component; and
A step of mixing the neutralized product of the alkyl-modified carboxyl group-containing polymer with at least one of an anionic emulsifier and a nonionic emulsifier;
The content of the anionic emulsifier is in the range of 0.05% by mass to 1% by mass (solid content), and the pH is in the range of 4 to 5.6,
The content of the nonionic emulsifier is in the range of 0.05 mass% to 1 mass% (solid content), and the pH is in the range of 4 to 13, the method for producing a gel composition.